In the art of plumbing water systems in residential, commercial and industrial buildings, it is common practice to provide water basins or sinks to receive and hold volumes of water in which, for example, cooking utensils, clothes and the like can be washed. Typically, such sinks are provided with drain openings at their bottoms. The drain openings are suitably connected with waste pipes that extend to suitable waste facilities such as sewer systems and septic tanks. As a general rule, dangerous and unpleasant gases are generated in sewer systems, septic tanks and the like. To prevent such gases from flowing back through the drain pipes and thence into the sinks, those means provided to connect the sinks with the drain pipes include gas or drain traps. Ordinary drain traps are tubular metal structures with U-shaped portions having lower tubular bases and upwardly projecting tubular legs. The U-shaped portions of the drain traps define trap basins in which limited volumes of water are contained to establish plugs through which gases tending to flow back through and from the drain pipes cannot flow.
A major shortcoming of metal drain traps of the general character referred to above resides in the fact that the drain traps are frequently subjected to subfreezing (below 32.degree. F.) temperatures which cause the water in their trap basin portions to freeze and establish ice plugs by or through which liquids or water in the sinks, cannot flow and drain and that render the sinks unservicable.
In addition to the above, the formation of ice plugs in drain traps frequently ruptures the drain traps or otherwise adversely affects the structural integrity thereof.
If an ice plug in a drain trap is not melted or otherwise reduced and/or removed from within the drain trap, the plug will remain in fixed place therein until the ambient temperature about the drain trap rises well above 32.degree. F. and remains at such an elevated temperature for a sufficient time to heat the drain trap and cause the plug therein to melt.
When ice plugs form in the trap basins of drain traps, it has long been common practice to accelerate the melting of those plugs by heating the drain traps, at and about the exteriors thereof. When heating drain traps to melt ice plug therein, it is not uncommon for persons to utilize blow torches, electric hair dryers, electric heating pads, electric radiant heaters and various other heat-generating devices as heat sources. Such practices are obviously highly inconvenient, inefficient and often unsafe.
Another and notable number of persons, in anticipation of the likelihood that ice will form in and plug the drain traps related to their sinks seek to prevent the formation of ice in the traps by introducing or pouring a volume of polyethylene glycol and other anti-freeze materials down the drains of their sinks and thence into the drain traps. The obvious shortcomings of such practices reside in the fact that the anti-freeze materials are quite costly and troublesome to use. Further, most anti-freeze materials are pollutants that should not to be disposed of in sewer systems and are such that if introduced into septic tanks they adversely affect or kill those microbes in such tanks are relied upon to reduce waste deposited therein.
In accordance with the foregoing, there is a recognized want and need for an improved drain trap structure which is such that when it is plugged by the formation of an ice plug therein, the ice plug can be easily, quickly and efficiently melted to establish a flow of water through the trap.